Notes:
This is one of the most pollution tolerant lichens known. It is the only one that grows in quantity in urban Pasadena. I’ve had the ID verified by Curtis Bjork. Look for it at the base of certain species of trees (magnolia, date palm, camphor, shamel ash, but not oak) where misted regularly by sprinklers (look for the green stain of algae). The ash in the yard of 874 S Oakland, the camphors on the north side of Fillmore between Euclid and Los Robles, and the date palms east of the entrance to Huntington Hospital are all particularly good places to see it. The apothecia are generally less than 1 mm wide.

Comments

Talk about making the most of what you have…glad to hear that at least some of our lichens are pollution tolerant; there’s certainly plenty of selective pressure to favor this species in urban and surrounding areas. Hope we don’t see more of it in montaine habitats throughout the Sierra…Sequoia/Kings Cyn., towering above the Central Valley, has some of the worst air quality in the Nation! A dubious distinction…